Preheat oven to 425. Spray a large baking sheet with cooking spray.
Pound the chicken breasts to ½ inch thickness. Chop into small ½-inch pieces.
Add flour and salt and pepper to taste to a small bowl and stir to combine. Whisk together the eggs and water in a second small bowl.
Combine bread crumbs and panko bread crumbs in a third small bowl and stir to combine. Place buffalo sauce in a fourth small bowl.
Toss the chicken pieces in the flour mixture. Next dip them in the egg wash bowl. Third, toss them in the bread crumbs. Lastly, dip the breaded chicken pieces in the buffalo sauce and place them 1-2 inches apart on prepared baking sheet. Once all of the chicken is on the baking sheet, spray with cooking spray.
Bake chicken bites for about 15-20 minutes until the chicken is cooked through and the outside is crispy.
Serve with blue cheese dressing (or ranch) and sprinkle with blue cheese crumbles if desired.